Presser for sewing machine and sewing machine

Abstract

A presser device for a sewing machine includes a first lever having a cloth pressing portion which is swingably mounted on a presser foot, the cloth pressing portion being swung so as to be switchable between a cloth pressing position and a raised position, a second lever having a support portion where the second lever is pivotally supported on an upper part of the first lever and an abutment which is normally in abutment with a needlebar assembly moved up and down, a first biasing member which biases the first lever so that the first lever is caused to pivot in such a direction that the cloth pressing portion becomes a cloth pressing position, and a second biasing member which biases the second lever so that the second lever is caused to pivot in such a direction that the abutment of the second lever is abutted against the needlebar assembly.

1. A presser device for a sewing machine which includes a presser bar, a needle and a needle bar assembly, the presser device comprising:
 a presser foot assembly which is connected to a lower end of the presser bar to press workpiece cloth to be sewn; 
 a first lever having a cloth pressing portion which is swingably mounted on the presser foot, the cloth pressing portion being swung so as to be switchable between a cloth pressing position where a part of the workpiece cloth located near a needle location of the needle is pressed by the cloth pressing portion when the needle is moved downward and a raised position to which the cloth pressing portion is raised from the cloth pressing position; 
 a second lever having a support portion where the second lever is pivotally supported on an upper part of the first lever and an abutment portion which is normally in abutment with the needlebar assembly moved up and down; 
 a first biasing member which biases the first lever so that the first lever is caused to pivot in such a direction that the cloth pressing portion becomes a cloth pressing position; and 
 a second biasing member which biases the second lever so that the second lever is caused to pivot in such a direction that the abutment portion of the second lever abuts against the needlebar assembly. 
 
   
   
     2. The presser device according to  claim 1 , further comprising a limiting mechanism which is provided on the first and second levers to limit a swinging range of the second lever, wherein the first and second biasing members have respective biasing forces set so that when the second lever is caused to pivot with upward movement of the needlebar, the first lever is swung after the swinging range of the second lever has been limited by the limiting mechanism. 
   
   
     3. The presser device according to  claim 1 , wherein a distance from a center of swinging movement of the first lever to the needle location of the needle is set so as to be equal to or shorter than a predetermined distance. 
   
   
     4. The presser device according to  claim 1 , wherein the first lever is detachably attachable to the presser foot assembly. 
   
   
     5. The presser device according to  claim 1 , wherein the second lever has a center of pivoting which is located in the rear of a vertical line including a center of axle of the needlebar assembly. 
   
   
     6. The presser device according to  claim 1 , wherein the needlebar assembly includes a needlebar and a needle clamp which fixes the needle to the needlebar, wherein the abutment of the second lever is formed into a bifurcated shape with the needle clamp being interposed between bifurcated portions thereof. 
   
   
     7. A sewing machine comprising:
 a presser bar; 
 a needle; 
 a needlebar assembly; 
 a presser foot assembly which is connected to a lower end of the presser bar to press workpiece cloth to be sewn; 
 a first lever having a cloth pressing portion which is swingably mounted on the presser foot assembly, the cloth pressing portion being swung so as to be switchable between a cloth pressing position where a part of the workpiece cloth located near the needle location of the needle is pressed by the cloth pressing portion when the needle is moved downward and a raised position to which the cloth pressing portion is raised from the cloth pressing position; 
 a second lever having a support portion where the second lever is pivotally supported on an upper part of the first lever and an abutment which is normally in abutment with the needlebar assembly moved up and down; 
 a first biasing member which biases the first lever so that the first lever is caused to pivot in such a direction that the cloth pressing portion becomes a cloth pressing position; and 
 a second biasing member which biases the second lever so that the second lever is caused to pivot in such a direction that the abutment of the second lever is abutted against the needlebar assembly. 
 
   
   
     8. The sewing machine according to  claim 7 , further comprising a first lever limiting mechanism provided on the presser foot and the first lever for limiting a swinging range of the first lever. 
   
   
     9. The sewing machine according to  claim 7 , further comprising a second lever limiting mechanism provided on the first and second levers for limiting a swinging range of the second lever. 
   
   
     10. The sewing machine according to  claim 9 , wherein the second lever limiting mechanism is disposed near a center of pivoting of the second lever.